Notes Payable, Long-Term Debt and Other Obligations (Conversion Rates on Convertible Debt) (Details) - Convertible Debt	12 Months Ended
	Dec. 31, 2016 $ / shares	Dec. 31, 2015 $ / shares
7.5% Variable Interest Senior Convertible Notes due 2019
Debt Instrument [Line Items]
Conversion price (in dollars per share)	$ 15.22	$ 15.22
Conversion ratio	0.065703	0.065703
5.5% Variable Interest Senior Convertible Debentures due 2020
Debt Instrument [Line Items]
Conversion price (in dollars per share)	$ 23.46	$ 23.46
Conversion ratio	0.04261825	0.04261825